Editing Hexaplex trunculus (section)

===As ancient dye===
The oldest known purple textiles were discovered in [[Syria]], dating back to the early second millennium BCE. Among these findings are textiles from a burial site at [[Chagar Bazar]], which date back to the 18th to 16th centuries BCE, as well as samples of preserved textiles found in gypsum at the Royal Palace of [[Qatna]].<ref>{{Cite journal |last1=James |first1=Matthew A. |last2=Reifarth |first2=Nicole |last3=Mukherjee |first3=Anna J. |last4=Crump |first4=Matthew P. |last5=Gates |first5=Paul J. |last6=Sandor |first6=Peter |last7=Robertson |first7=Francesca |last8=Pfälzner |first8=Peter |last9=Evershed |first9=Richard P. |date=December 2009 |title=High prestige Royal Purple dyed textiles from the Bronze Age royal tomb at Qatna, Syria |url=https://www.cambridge.org/core/journals/antiquity/article/abs/high-prestige-royal-purple-dyed-textiles-from-the-bronze-age-royal-tomb-at-qatna-syria/69EC1A74600EC74AAAC26D2F585ACF5A |journal=Antiquity |language=en |volume=83 |issue=322 |pages=1109–1118 |doi=10.1017/S0003598X00099397 |s2cid=162563421 |issn=0003-598X|url-access=subscription }}</ref><ref>{{Cite journal |last1=Sukenik |first1=Naama |last2=Iluz |first2=David |last3=Amar |first3=Zohar |last4=Varvak |first4=Alexander |last5=Shamir |first5=Orit |last6=Ben-Yosef |first6=Erez |date=2021-01-28 |title=Early evidence of royal purple dyed textile from Timna Valley (Israel) |journal=PLOS ONE |language=en |volume=16 |issue=1 |pages=e0245897 |doi=10.1371/journal.pone.0245897 |issn=1932-6203 |pmc=7842898 |pmid=33507987 |doi-access=free |bibcode=2021PLoSO..1645897S }}</ref><ref>{{Cite journal |last=Karapanagiotis |first=Ioannis |date=January 2019 |title=A Review on the Archaeological Chemistry of Shellfish Purple |journal=Sustainability |language=en |volume=11 |issue=13 |pages=3595 |doi=10.3390/su11133595 |issn=2071-1050 |doi-access=free }}</ref> 
[[File:Tunisian Purple.jpg|thumb|260px|left|Carthaginian murex pigment from Tunisia]]
[[File:Purple_Purpur_(retouched).jpg|thumb|Purple dyed fabric]]
The ancient method for mass-producing blue dye from ''Hexaplex trunculus'' has not been successfully reproduced. Today, with stronger reduction agents which are more transparent, it is possible to break the original purplish hue molecule and degrade it by introducing it to UV sun rays, resulting in a more blue color. Therefore, archeologists have confirmed ''Hexaplex trunculus'' as the species used to create the purple-blue dye; large numbers of shells were recovered from inside ancient live-storage chambers that were used for harvesting. Apparently, 10 to 12,000 shells yielded only one gram of dye. Because of this, the dye was highly prized. Also known as ''Royal Purple'', it was prohibitively expensive and was only used by the highest ranking aristocracy.

A similar dye, ''[[Tyrian purple]]'', which is purple-red in color, was made from a related species of marine snail, ''[[Bolinus brandaris|Murex brandaris]]''. This dye (alternatively known as ''imperial purple'', see [[purple]]) was also prohibitively expensive.

Jews may have used the pigment from the shells to create a sky-blue, ''[[tekhelet]]'', dye to put on the [[tzitzit|fringes]] that the [[Torah]] specifies for the corner of the [[Tallit|prayer shawl]]. This blue dye would have been made by taking the yellow dye solution and letting it sit in the sunlight, and then dipping the wool in it. This dye was lost to history until it was rediscovered by Otto Elsner, a professor at the [[Shenkar College of Fibers]] in [[Haifa]]. Since then, it has been re-introduced as the authentic ''tekhelet'' and has once again been reinstated to the Jewish garment <ref>{{Cite web|url=http://tekhelet.com/tekhelet/introduction-to-tekhelet/|title=Tekhelet 101}}</ref> although only with limited acceptance.